.hide-float-bg{
    position: fixed;
    top:0px;
    left:0px;
    right:0px;
    bottom: 0px;
    background: rgba(0,0,0,0.5);
    z-index: 8;
    display: none;
}
.show-float-bg{
    position: fixed;
    top:0px;
    left:0px;
    right:0px;
    bottom: 0px;
    background: rgba(0,0,0,0.5);
    z-index: 8;
}